Material of construction.



UNTTED STATES PATENT ()FFICE.

EDWVIN THAOIIER, OF NEW YORK, N. Y.

MATERIAL OF CONSTRUCTION.

SPECIFICATION forming part of Letters Patent N 0. 714,971, dated December 2, 1902.

Application filed August I 1902. Serial No. 117,925. (110 model.)

To aZZ whom it may concern:

Be it known that LEDWIN THAOHER,a citizen of the United States, and a resident of the city of New York, in the county of New York and State of New York,have invented certain new and useful Improvements in Material of Constructiomof which the following is a specification.

This invention is in the nature of a compound bar or unit of construction to be used in the building of bridges, docks, beams, girders, floors, roofs, walls, and any other structn re, the object of the invention being to provide a compound unit or bar of strength, simplicity, and cheapness and one which is peculiarly adapted for use under certain conditions.

The invention consists in a compound bar or unit of construction having a core of peculiar form embedded in concrete, and in the core for such a unit, as fully described, and hereinafter specifically pointed out in the claims.

On January :21, 1902, there was issued to me Letters Patent of the United States No. 691,416 for a material of construction consisting of a metal bar for use as a core to be embedded in concrete, flattened and laterally extended at intervals without material alteration of its cross-sectional area.

I have found the form of unit described and claimed in the Letters Patent above referred to especially useful where expensive kinds of concrete were employed and the cost of the material was a serious item. Under some circumstances of use, however, especially where a cheap concrete is employed in which to embed the iron bar,it is important to secure excessive holding power. Under such circumstances it is undesirable to retain the uniformityof crosssectional area which was the distinguishing feature of the core-bar of the patent referred to, and I find it advisable under such circumstances to vary the sectional area, and the bar havingsuch variation of area with and without its envelop of concrete is the subj eat-matter of this application. I have likewise discovered that the strength of a bar squashed or flattened out laterally so that its cross-sectional area is at places diminished as compared with other places is not affected in proportion to the loss of cross-sectional area. For instance,

I may lessen the cross-sectional area at one point in such a squashed bar to the extent of twenty per cent., and at the same time I find that the loss in tensile strength does not exceed seven per cent. Of course the entire bar has the strength of its weakest point only. By varying the cross-sectional area of the bar I find that I secure another advantage. For example, I can make sharper shoulders and wider flanges when I make no attempt to have the cross-section uniform. I therefore prevent more efficiently the rupture of the concrete in which the bar is embedded.

In carryingout myinvention I may make the cores of a numberof forms; butIhave deemed it desirable to illustrate only two or three forms, as the principle of the invention may be readily gathered from them.

In the accompanying drawnings, Figure 1 represents a longitudinal section of one embodiment of my invention, the core being shown in elevation. Fig. 2 represents alongitudinal section of the same in a plane at right angles to that of the section shown in Fig. 1. Fig. 3 represents a transverse section on the plane of line 3 3 in Fig. 1, and Fig. 4. similarly represents a transverse section on the plane of line 4 l in Fig. 2. Fig. 5 represents a longitudinal section of another embodiment of my invention, the core being shown in elevation. Fig. 6 represents a longitudinal section of the same on the plane at right angles to the section shown in Fig. 5. Fig. 7 represents a transverse section on the plane of the line 7 7 in Fig.5, and Fig.8representsa transverse section of the same on the plane of the line 8 8 in Fig. 6.

Referring to the figures, a. represents a metal bar, which may be originally of any cross-sectional form-for instance, circular, square, rectangular, or elliptical. By operating upon the original bar by rolling, hammering, squeezing, forging, or other mechanical manipulation, with or without the use of dies, the metal of the original bar may be displaced, so that its form in section is flattened in one direction and laterally extended in another, as is clearly shown in Figs. 3, 4., 7, and 8. Subsequent manipulations after the first may so alter the form of the core as to leave nothing remaining of its original con- For instance, I show in Figs. 1,

figuration.

2, 3, and 4 a core which was originally either round or square, but which has become distorted at the portions 17 b b b, &c., so asto form, in eflect, irregular globes, while the intermediate square portions of the bar c c c c c, 850., have been converted practically into flattened disks, although the adjacent portions of each part of the bar are integral. It will be observed that no attempt has here been made to preserve uniformity of cross-section as between the parts I) and 0, but that the attempt has been made rather to form abrupt shoulders, as at d d e e, 850., so as to prevent the longitudinal or lateral displacement of the bar. In Figs. 5, 6, '7, and 8 I illustrate a form of the core in which the square shape of the original bar has been retained in the sections fff f ff and the flattened or distorted portions 9 g g g g ghave been madein the shape of flat disks somewhat similar to the portions 0 c c c in Figs. 1, 2, 3, and 4. In the construction illustrated in this second group of figures the shoulders h h are not so abrupt, but still afford great resistance to longitudinal or lateral displacement.

Of course it will be understood that the forms of cores illustrated are merely examples of forms of distortions which may be employed in carrying out myinvention and that other forms may be employed, provided the principles above enunciated have been followed in their formation. Such forms may be made by restricting or permitting the escape of the material sidewise or longitudinally in the process of forming the bar, as will readily be understood by those skilled in this art.

What I claim as new is 1. A metal bar for use as a core for embedding in concrete flattened and laterally extended at intervals whereby the cross-sectional area of the bar is materially altered.

2. A metal bar for use as a core for embedding in concrete flattened and laterally eX- tended at intervals in different longitudinal planes whereby the cross-sectional area of the bar varies at its different portions.

3. A metal bar, for use as a core for embedding in concrete, flattened and laterally extended at intervals, the longitudinal plane of each flattened portion being at an angle to that of the adjacent laterally-extended portion in either direction of the bar and each flattened portion different in cross-sectional area from that of the adjacent laterally-extended portion in either direction.

4. A compound bar or unit of construction consisting of a metal bar flattened and later ally extended at intervals whereby the crosssectional area of the bar is materially altered, embedded in an envelop of concrete.

5. A compound bar or unit of construction consisting of a metal bar flattened and laterally extended at intervals in different longitudinal planes whereby the cross-sectional area of the bar varies at its difierent portions, embedded in an envelop of concrete.

,6. A metal bar for use as a core for embedding in concrete squashed at intervals and formed by permitting the material of the bar to escape sidewise whereby two or more shoulders are formed between adjacent sections of the bar by the squashing process and two, or more shoulders by the sidewise escape ofthe material.

7. A compound bar or unit of construction consisting of a metal bar squashed at intervals and formed by permitting the material of the bar to escape sidewise whereby two or more shoulders are formed between adjacent sections of the bar by the squashing process and two or more shoulders by the sidewise escape of the material embedded in an envelop of concrete.

8. A compound bar or unit of construction consisting of a metal bar flattened and later: ally extended at intervals, the longitudinal plane of each flattened portion being at an angle to that of the adjacent laterally-extended portion in either direction of the bar and each flattened portion differing in cross-sec tional area from that of the adjacent laterally-extended portion in either direction, embedded in an envelop of concrete.

Witness my hand this 30th day of July, 1902, at the city of New York, in the county and State of New York.

EDWIN THACHER. 

